The present invention relates to surgical clip appliers embodied as an instrument having a supply of clips for rapidly deploying several clips in closing severed blood vessels and other small fluid carrying ducts in surgical procedures. There are many different designs for surgical clip applicators for a variety of surgical procedures including both open surgery and laparoscopy in which a clipping appliance fits through a trocar tube into a body cavity where the clips are applied.
A surgical clip applicator comprises an operating handle and clip applying mechanism having an operating cycle in which operating levers are squeezed together and released. In this operating cycle, a clip is applied in surgery and the clip applicator jaws are reloaded with a single clip from a clip supply channel for clip application in the next cycle. The applicator provides a moveable clip supply channel containing a line of clips that are released seriatim. The supply channel integrates a clip pusher and an escapement or clip stop spring in a single unit.
A well-known hazard with clip appliers is a condition of releasing a partially closed clip in a surgical site. This condition results when operating handles are given a partial pull or closing and then released. The partial pull crimps but does not close a clip located in the instrument jaws. When partially pulled handles of some older instruments are released, the instrument jaws re-open and the partially closed clip falls from the jaws into the surgical site.
This invention provides an anti-backup mechanism for a repeating multi-clip applier to prevent this operating hazard.
The present invention also relates generally to mechanical devices used in applications other than clip appliers, where such devices have reciprocal motion in one or more components, and where it is desirable for proper operation of the devices to ensure that full reciprocal motion of components occurs in operating or using the devices. The invention ensures that reciprocal translators (i.e., that component of the device which undergoes reciprocal motion) forming part of a mechanical device move through the full reciprocal excursion assigned to the translator as a component of a mechanical device. Specifically, the invention prevents reversal of movement of a reciprocal translator at a point intermediate the full excursion assigned to the translator. If a translator comes to rest at a point intermediate full excursion, the anti-backup device of the invention ensures that the translator is restricted to resuming movement only in the same direction as before it came to rest.